Process of treating artificial silk made from viscose



Patented July 15, 1930 i JNE'E'ED ST-.TES PTEN'F GFF'ECE KARL LEUCHS, OF BERLIN-ZEHLENDORF, GERMANY PROCESS F TBEATING ARTIFICIAL SILK MADE FROM 'VISCOSE Application led October 10, 1927, Serial No. 225,239, and in Germany July 5, 1926.

My invention relates to improvements in spools, and it is my intention to cancel from the process of treating artificial silk from visthe said application the claims relating to cose.- the treatment of the silk spun by the cen- In a copending application Ser. No. trifugal spinning process, which modification 178,012, filed by me March 24, 1927, I have of the process is the subject matter of the 55 described a process by means of which the present application for patent. treatment of the artificial silk following the As appears from the foregoing description formation vof the thread from viscose by coof the process, it is not necessary to transagulation is carried out While the silk is in form the silk into a skein. Further, one of the form of a coherent mass, the said silk the tvvo drying operations heretofore necese0 being either treated on a foraminated spinsary is dispensed with, because all the operning spool, or in the form of an annuular ations are performed without intermediate v body obtained by spinning the thread by the drying, and drying is necessary only at the centrifugal spinning process into a rotary end of the Whole operation. Thus, immedibox. The process is important for the reaately from the annuular body of silk obtained c5 son that it is not necessary first to transform by the centrifugal spinning process a thread the spun silk into a skein and to treat the is obtained which is ready for sale, which thread in the form of a skein in which it is thread can be formed into a skein. The prodsubject to injury. As has been described in uct thus obtained is superior to the product the said application, Where the carrier of the obtained by the method now in use, and more 70 body -of artificial silk is made from alumiparticularly it can be more readily spun on num, the said treatment of *the body of silk bobbins, because the thread has not been incan be carried out if the desulfurizing bath jured by the various operations to which it 'consists of diluted hot solutions of the salts has been subjected. In my improved process of weak acids having alkaline reaction, such the silk is practically not injured in a me- 75 for example as the sodium, potassium, o r chanical Way, because all the operations are ammonium salts of the acids of the acetic performed on the same apparatus, that is acid group, the carbonio acid, the boric acid, the carrier of the cylindrical body produced and the phosphoric acid, the most approprion the centrifugal spinning machine. Furate dgsulgipiainggnediumhavingbeen found ther, the finished thread can be directly spun so to be sulfite of sodium (Na2SQ3), which has on a cross-Wound bobbin, 'a straight bobbin,

'a 'certain bleachfig'ffatiom'and affects the and the like, so that one operation, viz. the threads in a less degree than the sulfide of forming of the thread into a skein, is dissodium ordinarily used as a desulfurizing mepensed with.

dium. By the said sulfite the sulphur is dis- In carrying out my improved process I sa solved While forming sodium-thiosulfate. cause the liqulds successively to flow through' Since the said salts do not affect the aluminum the body of silk by difference of pressure, in an appreciable Way, the silk can be desulfor which purpose foraminated carriers are furized and further treated on the usual used for treating the silk. Suitable methods 40 spools or other carriers made form aluminum. of causing the liquids to fiow through the o0 Thus the thread can be freed of acid, desulmass of silk by difference of pressure are furized, and/further treated by means of known in the art. One method consists in sulfuric acid and the usual softening media causing the liquid to flow through the mass such as soap and oil While being on the alumiof-silk by centrifugal action, the carrier connum spinning spool, or in the form ofthe taining the mass of silk being placed axially said cylindrical body produced by the cenon a suitable support or table adapted to be trifugal spinning operation. rotated at high velocit and the liquid being In the said copending application I have delivered into the bo y of silk and thrown claimed m improved process as applied to outwardly therethrough and through the fothe metho of treating silk spun on spinning raminated carrier.

I am aware that it has heretofore been proposed to pass certain liquids necessary for treating a body of silk obtained from viscose by the centrifugal spinning process through the said body by centrifugal action, and I do not claim the method of drivin r the liquid through the body of silk by centriu gal action per se. But what I claim is the method of treating the body of silk obtained by the centrifugal spinning process and supported on a carrier made from aluminum, in which one of the aforesaid media, and more particularly sulfite of sodium, are used for desulfurizing the silk.

n order that my invention be more clearly understood an apparatus suitable for putting the process into effect has been illustrated in the accompanying drawing, in which,

Fig. l, is a sectional elevation of the apparatus, and

Fig. 2, is a sectional elevation showing a modification.

In Fig. l, the cylindrical boxadapted to have the thread of artificial silk coming from the spinning nozzles deposited therein has received the reference character a. The said box is formed with a foraminated cylindrical wall` the foraminations having been indicated by the letter b, and it is fixed to a base c formed with an axial bore d. After a body of silk e has been spun the box a containing the said body is placed axially on a centrifugal machine. As shown in Fig. l, the said centrifugal machine may consist for example of a tzble f having an axial stud projecting therefrom and mounted at the top end of a spindle h. The said spindle is mounted in bearings i and j, and it carries a driving member which for the purpose of illustration has been shown as a pulley k.

Into the box a a pipe m is passed, which is formed at its bottom with bores n for the discharge of the liquids therethrough. So far the apparatus is known in the art.

Referring now to the novel features, the box a is made from aluminum, and the desulfurizing medium supplied through the pipe m consists of a diluted hot solution of one of the aforesaid salts such as sulfite of sodium.

In the operation of the apparatus the box a is placed on the table f, and the pi e m is passed downwardly into the same. ow the table f and the box a are rapidly rotated, and the baths necessary for treating the body of silk e are successively passed under pressure through the pipe m, from which they are delivered in radial direction through the bores fn.

After the silk has thus been treated it is dried while within the box, or otherwise. Finally'the finished silk is directly spun on cross-wound bobbins, straight bobbins, and the like, or it is formed into skeins, Whereupon it is ready for sale.

In Fig. 2 I have shown a modification in which a box a adapted to have the silk spun therein is provided with a removable foraminated lining or case o made from aluminum. For treating the silk the case o is removed from the box a and the centrifugal spinning machine, and it is placed on a centrifugal machine similar to the one illustrated in Fig. E, whereupon the liquids are successively passed through the body of silk while rapidly rotat' ing the same in the manner described with reference to Fig. l.

In this modification of the method the box a may be made from any suitable material.

In another modification of the process only some. of the liquids are passed through the body of silk contained within the, box a or o, and the artificial silk which has thus been partly treated is spun on a foraminated bobbin, whereupon the treatment is completed by assing` the remaining baths through the said obbin and the body of silk spun thereon. If the step of desulfurizing the silk is performed on the said bobbin, the bobbin is made from aluminum, and the desulfurizing medium consists of a solution of one of the aforesaid salts such as sodium sulfite.

I claim:

l. The herein described process of manufacturing artificial silk, which consists in spinning viscose by the centrifugal spinning process into a rotary box having a foraminated wall made from aluminum, and caus ing a diluted hot solution of a salt of a weak acid having alkaline reaction to flow through the silk and the foraminated wail of said box.

2. The herein described process of manufacturing artificial silk, which consi'sts'in spinning viscose by the centrifugal spinning process into a rotary box having a foraminated wall made from aluminum, and causing a solution of sodium sulfite to How through the silk and the foraminated wall of said box.

In testimony whereof I hereunto afiix my signature.

KARL LEUCI-IS. 

